The estimation of structural properties for molten CaO-CaF ₂-SiO₂ system by molecular dynamics simulations

The structural analysis of CaO-SiO₂-CaF₂ melts was carried out by the molecular dynamics simulation method using the newly optimized parameters which could properly reproduce their densities. The Busing approximation of the Born-Mayer-Huggins form was used as the pair potential during the molecular dynamic simulation. The periodic boundary conditions were employed for the basic cells containing 1250-1800 atoms under the isobaric and isothermal conditions. The calculations were conducted 10000 steps at both temperatures and the cooling rate was set to be 0.1Ks^-1. The running coordination number of j ions within the nearest neighbor of an i ion was defined as N_i-j and calculated by assuming that r was equal to the tail end of the first peak of g_i-j(r). The substitution of CaO for CaF₂ enhances the polymerization of the melt up to 25 mol% of CaF₂ and suppressess it at the higher concentration.